Plot hole: In the scene where Westley is tortured to extremity, he screams, and upon hearing him scream, Inigo is instantly able to identify Westley and that he is in love with someone about to marry. You could say Fezzik told him, but how did Fezzik know? For all they knew, he was just a pirate after a prize.
Suggested correction: He doesn't instantly identify Westley; he identifies the sound of ultimate suffering. He surmises that it must be Westley because he can't think of anyone else who would have cause for ultimate suffering. By now the news would have spread that Humperdink's men apprehended a pirate claiming to be Buttercup's true love. Inigo was simply putting two and two together.
Plot hole: In the morning at the motel, the vampires have a big shoot-out with local law enforcement, which results in one at least one cop being killed. But when they escape, the police don't bother pursuing them or even giving them a another thought. Even for an 80's film, this is beyond ludicrous.